1.连接数据库配置

dbConfig.js

module.exports = {
  mysql: {
    host: '127.0.0.1',//本地
    user: 'root', //数据库账号
    password: '123456',//数据库密码
    database: 'mhzqx',//数据库名
    port: 3306 //数据库端口号
  }
}

2. 安装mysql 插件

npm i mysql -S

3.封装连接mysql

connection.js

var mysql = require('mysql')
var dbConfig = require('../db/dbConfig')
var pool = mysql.createPool(dbConfig.mysql)

module.exports = function (sql) {
    return new Promise(function (resolve, reject) {
        pool.getConnection(function (err, conn) {
            if (err) {
                reject(err);
            } else {
                conn.query(sql, function (err, res) {
                    //释放连接
                    conn.release();
                    //传递Promise回调对象
                    resolve({
                        err,
                        data: res
                    });
                });
            }
        });
    });
};

4. 使用

good.js

//引入
const express = require('express');
const router = express.Router();
let conn = require('../../db/conection')

// 根据商品id获取商品信息
router.get("/getGoodsByGid", async (req, res) => {
    let {gid} = req.query
    let sql = `select * from goods where GID=${gid}`
    let result = await conn(sql)
    if (result.data) {
        res.json({
            status: 200,
            msg: '获取成功',
            data: result.data[0]
        })
    } else {
        res.json({
            status: -1,
            msg: '获取失败'
        })
    }
})

module.exports = router;